The present invention relates to a reproduction apparatus comprising an electrostatic copying machine or the like and a sorting means for receiving copies discharged by the copying machine in either of two positions on the sorting means. The present invention may be applied to any type of reproduction apparatus which produces reproductions of original documents in sheet form such as an offset printing machine, a mimeograph machine, etc.
A prior art example of such an apparatus is disclosed in Japanese patent publication No. 44-2169 and comprises an electrostatic copying machine which discharges copies into a sorting unit having a tray which is horizontally pivotal between two positions. After a copying operation is completed and the one or more copies of a single original document have been discharged into the tray, an electrical sort signal is generated causing the tray to pivot from whichever position it currently occupies to the other position. This operation will be herein referred to as toggling. After one or more copies are produced of the next original document and the copies are discharged into the tray, the tray is toggled to the other position. In this manner, the copies of the first document are stacked in one position on the tray while the copies of the second document are stacked in a second position on the tray which is angularly offset from the first position. The copies of the third document are stacked in the first position, the copies of the fourth document are stacked in the second position, etc. In other words, the copies are sorted according to the original documents.
Although this prior art apparatus has utility in some applications, it suffers from several problems and is not applicable to all modes of operation of a typical electrostatic copying machine. Since the tray is toggled after each copying operation, the sorting operation is meaningless where only one copy is produced of each original document. In such a case the sorting operation is a nuisance since the copies are received on the tray in alternating positions and must be aligned by hand after all the copies have been produced.
In an electrostatic copying machine provided with an automatic original document feed unit or device, the sorting operation of the prior art apparatus is not only undesirable for the reason stated immediately hereinabove but also because since in an automatic copying operation it is desirable to sort the copies in sets. In other words, a plurality of original documents are fed through the feed unit sequentially and a single copy is made of each document. Typically, the documents will be pages of a manuscript and therefore constitute a set. It is desired to stack all of the copies of the set in one position, toggle the tray and then stack the copies of the next set of documents in the other position. However, the prior art apparatus is not capable of this operation but instead meaninglessly toggles the tray after each copy is produced.
In accordance with the normal operation of such a prior art apparatus, the tray is toggled after the last copy is produced. This final operation is not only unnecessary but may cause injury to an inexperienced apparatus operator who attempts to remove the copies from the tray as the tray is being toggled. This problem will occur most frequently when a new operator makes only one copy of a single document, since the movement of the tray will be completely unexpected.
Another problem with such a prior art apparatus lies in the basic design of the sorting unit. Since the tray, which protrudes externally from the copying machine and is large in size, is toggled repeatedly, there is a substantial danger that a part of the body or clothing of the operator will become entangled in the mechanism and be damaged. Due to the large size of the tray, a large force is required to toggle the same. As yet another hazard, due to the large size of the tray and the large pivotal moment which can be applied thereby to the drive mechanism as the result of the operator or some object bumping the tray, the drive mechanism is subject to constant damage.